الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
Fayoum Depression looks like an oasis of a particular nature with unique geographical and topographical features as the environment is a mix of agricultural nature, desert and coastal (ARCADIS, 1999).Water is delivered to Fayoum in a limited quota from the Nile through Bahr Youssef..
Niille watterr iis miixed wiitth drraiinage watterr tthrrough seven majjorr
miixiing sttattiions fforr iirrrriigattiion purrposes iin Fayoum.. However, aquatic ecosystems suffer the consequences of human activities. Activities such as mining, agriculture and industrial plants with large urban settlements systematically produce pollutants that are discharged in a dissolved form or suspended in material in rivers, thus significantly decreasing water quality and increasing the ecological risk to human health (Yi et al., 2011).
It is obvious that Fayoum depression has various water bodies differ in their quality. The number of plant species varied from canal or drainage to another. Many species with various life forms and different floristic categories are representing the recent status of the aquatic macrophytes in canals and drainages.
The factors that govern the richness of the vegetation along the banks of rivers and other water bodies are still poorly
Introduction
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understood (Nilsson et al. 1989). In Egypt, such studies have received little attention.
In natural aquatic ecosystems, metals occur in low concentrations, normally in the nanogram to microgram per liter level. In recent times, however, the occurrence of metal contaminants especially the heavy metals in excess of natural loads has become a problem of increasing concern. Watterr conttamiinattiion
wiitth heavy mettalls iis serriious,, as tthey arre ttoxiic and arre nott
biiodegrradablle.. All water resources of Fayoum are contaminated with Cd and Ni, whilst their Pb concentrations are generally within